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A > large burst of SRv6 nexthops outruns the refill worker and will fail > with -ENOMEM despite there being free memory: > > percpu: allocation failed, size=40 align=8 atomic=1, atomic alloc > failed, no space left > > Batching 20000 RTM_NEWNEXTHOP under QEMU gave 10-109 failures per run > before, none after. > > This commit converts the allocations reached through ops->build_state() > and are called after the rcu_read_unlock(): > > - ila_build_state(), ioam6_build_state(), rpl_build_state(), > seg6_build_state(): build_state ops > - bpf_parse_prog(): only called from bpf_build_state() > - lwtunnel_state_alloc(): only called from build_state ops (also > affects mpls, ip/ip6 tunnel, xfrmi and seg6_local) > > Signed-off-by: Max Boone > Reviewed-by: Debabrata Banerjee > Reviewed-by: Nick Hudson Reviewed-by: Ido Schimmel